After pruning files trying to figure out why server usage is so high even during idle and no players on, I discovered that the Mineshaft.dat file was the source of it.
Before deletion the file was 839KB vs 14KB for the next largest file, Strongholds.dat.
As for process usage before deletion the server will run at 60% usage on idle, after 20%. Running on a dual core@3GHZ that's a whopping 2.4GHZ of process generated permanently from the single file.
I've tested the server file and pruned the .dat file on another of my computers (x6core) and it showed the same results.
I may be wrong but I don't think the Mineshaft structure data file shouldn't be generating 2/3rds of a server's processes.
Attached Image is a before and after of resources while on idle.
Not sure what causes this (Process loop?) but I hope this report is helpful.